ObjectiveTo investigate the early effects of acellular xenogeneic nerve combined with adipose-derived stem cells (ADSCs) and platelet rich plasma (PRP) in repairing facial nerve injury in rabbits.MethodsThe bilateral sciatic nerves of 15 3-month-old male Sprague-Dawley rats were harvested and decellularized as xenografts. The allogeneic ADSCs were extracted from the neck and back fat pad of healthy adult New Zealand rabbits with a method of digestion by collagenase type Ⅰ and the autologous PRP was prepared by two step centrifugation. The 3rd generation ADSCs with good growth were labelled with CM-Dil living cell stain, and the labelling and fluorescence attenuation of the cells were observed by fluorescence microscope. Another 32 New Zealand rabbits were randomly divided into 4 groups and established the left facial nerve defect in length of 1 cm (n=8). The nerve defects of groups A, B, C, and D were repaired with CM-Dil-ADSCs composite xenogeneic nerve+autologous PRP, CM-Dil-ADSCs composite xenogeneic nerve, xenogeneic nerve, and autologous nerve, respectively. At 1 and 8 weeks after operation, the angle between the upper lip and the median line of the face (angle θ) was measured. At 4 and 8 weeks after operation, the nerve conduction velocity was recorded by electrophysiological examination. At 8 weeks after operation, the CM-Dil-ADSCs at the distal and proximal ends of regenerative nerve graft segment in groups A and B were observed by fluorescence microscopy; after toluidine blue staining, the number of myelinated nerve fibers in regenerated nerve was calculated; the structure of regenerated nerve fibers was observed by transmission electron microscope.ResultsADSCs labelled by CM-Dil showed that the labelling rate of cells was more than 90% under fluorescence microscope, and the labelled cells proliferated well, and the fluorescence attenuated slightly after passage. All the animals survived after operation, the incision healed well and no infection occurred. At 1 week after operation, all the animals in each group had different degrees of dysfunction. The angle θ of the left side in groups A, B, C, and D were (53.4±2.5), (54.0±2.6), (53.7±2.4), and (53.0±2.1)°, respectively; showing significant differences when compared with the healthy sides (P<0.05). At 8 weeks after operation, the angle θ of the left side in groups A, B, C, and D were (61.9±4.7), (56.8±4.2), (54.6±3.8), and (63.8±5.8)°, respectively; showing significant differences when compared with the healthy sides and with the values at 1 week (P<0.05). Gross observation showed that the integrity and continuity of regenerated nerve in 4 groups were good, and no neuroma and obvious enlargement was found. At 4 and 8 weeks after operation, the electrophysiological examination results showed that the nerve conduction velocity was significantly faster in groups A and D than in groups B and C (P<0.05), and in group B than in group C (P<0.05); no significant difference was found between groups A and D (P>0.05). At 8 weeks after operation, the fluorescence microscopy observation showed a large number of CM-Dil-ADSCs passing through the distal and proximal transplants in group A, and relatively few cells passing in group B. Toluidine blue staining showed that the density of myelinated nerve fibers in groups A and D were significantly higher than those in groups B and C (P<0.05), and in group B than in group C (P<0.05); no significant difference was found between groups A and D (P>0.05). Transmission electron microscope observation showed that the myelinated nerve sheath in group D was large in diameter and thickness in wall. The morphology of myelin sheath in group A was irregular and smaller than that in group D, and there was no significant difference between groups B and C.ConclusionADSCs can survive as a seed cell in vivo, and can be differentiated into Schwann-like cells under PRP induction. It can achieve better results when combined with acellular xenogeneic nerve to repair peripheral nerve injury in rabbits.
Microsurgery has always been the main treatment for large vestibular schwannomas. With the progress of microsurgical technique and neuroimaging, the application of the intraoperative physiological monitoring technology, as well as the popularization of the concept of minimally invasive neurosurgery, the current development trend of surgery for vestibular schwannomas is to realize both the maximal tumoral resection and the maximal preservation of facial nerve function, which puts more emphasis on the improvement of quality of life. It is still a challenge for neurosurgeons to resect the tumor to the maximum extent and preserve the nerve function as well. In view of this background, the strategy of " near-total resection” and " subtotal resection” combined with stereotactic radiotherapy has been more and more accepted in the past years. However, as a neurosurgeon, the ultimate goal should be " gross-total resection of tumor” and preservation of the nerve function as well. For those tumors severely adherent to neurovascular structure, " near total resection” might be a rational choice. Meanwhile, long-term follow-up should be conducted to clarify the biological behavior of tumor residues, as well as the necessity and long-term effect of stereotactic radiotherapy.
Objective Using chemically extracted acellular methods to treat extracranial section of the canine whole facial nerve, to evaluated its effects on nerve structure and the removal extent of Schwann cells and myel in. Methods Twenty whole facial nerves were exposed from 10 canines [weighing (18 ± 3) kg]. The extracranial trunk of canine facial nerve and its branches (temporal branch, zygomatic branch, buccal branch, marginal mandibular branch, and cervical branch) were dissected under l ight microscope. Twenty facial nerves were divided into the experimental group (n=12) and control group (n=8) randomly. In experimental group, the nerve was extracted with the 3%TritonX-100 and 4% sodium deoxycholate. In control group, the nerve was not extracted. HE staining and immunofluorescence histological stainings for Hoechst33258, P75, Zero, and Laminin were performed. Results After histological staining, it was found that myel in and Schwann cells were removed from the facial nerve while the basal lamina tube remained intact. The whole canine facial nerves (one nerve trunk and multiple nerve branches) had the similar result. Conclusion The canine whole facial nerve has natural structure (one nerve trunk and multiple nerve branches) by extracted with chemically extracted acellular methods, so it is an available graft for repairing the defect of the whole facial nerve.
Objective To investigate the effectiveness of facial nerve-sublingual nerve parallel bridge anastomosis for facial nerve injury resulting from closed temporal bone fractures. Methods Between January 2017 and December 2019, 9 patients with facial nerve injury resulting from closed temporal bone fracture caused by head and face trauma were treated. Among them, 5 patients were treated with facial nerve-sublingual nerve parallel bridge anastomosis (operation group), and 4 patients were treated with neurotrophic drugs combined with rehabilitation exercise (conservative group). There was no significant difference in gender, age, side, cause of injury, duration of facial nerve injury before surgery, House-brackmann grading (hereinafter referred to as HB grading) of facial nerve injury, and other general information between 2 groups (P>0.05). HB grading was used to evaluate the improvement of facial nerve function before and after treatment. At the same time, facial nerve neuroelectrophysiological test was performed to evaluate the electrical activity of facial muscles before and after treatment. Tongue function, atrophy, and tongue deviation were evaluated after nerve anastomosis according to the tongue function scale proposed by Martins et al. Results Patients in both groups were followed up 12-30 months, with an average of 25 months. None of the 5 patients in the operation group showed symptoms such as tongue muscle atrophy, tongue extension deviation, hypoglossal nerve dysfunction (mainly including slurred speech, choking with water), postoperative infection, bleeding, lower limb muscle atrophy or lower limb motor dysfunction after sural nerve injury. Postoperative skin sensory disturbance in lateral malleolus area was found, but gradually recovered to normal. During the follow-up, facial nerve and sublingual motor neurons were innervated to paralyzed facial muscle in the operation group. At last follow-up, the HB grading of 5 patients in the operation group improved from preoperative grade Ⅴ in 2 cases, grade Ⅵ in 3 cases to grade Ⅱ in 3 cases, grade Ⅲ in 1 case, and grade Ⅳ in 1 case. And in the conservative group, there were 1 patient with grade Ⅴ and 3 patients with grade Ⅵ before operation, facial asymmetry continued during follow-up, and only 2 patients improved from grade Ⅵ to grade Ⅴ at last follow-up. There was significant difference in prognosis HB grading between the two groups (t=5.693, P=0.001). In the operation group, the amplitude and frequency of F wave were gradually improved, and obvious action potential could be collected when the facial muscle was vigorously contracted. On the contrary, there was no significant difference in neuroelectrophysiological results before and after treatment in the conservative group. ConclusionFacial nerve-sublingual nerve parallel bridge anastomosis can effectively retain the integrity of the facial nerve, while introducing the double innervation of the sublingual nerve opposite nerve, which is suitable for the treatment of severe incomplete facial nerve injury caused by closed fracture.
Objective To evaluate the clinical effect of end-to-end neurorrhaphy following rapid expansion of the nerve in repairing facial nerve defect. Methods From August 2000 to February 2005, 9 patients suffering from facial nerve defect were treated by the surgical method. The defect was caused by traffic injury(4 cases) , by cutting injury (2 cases) and falling wound(1 case). Seven cases showed prominent facial paralysis. The other 2 cases were invaded by parotid carcinoma, without remarkable paralysis. One case had unibranch defect, and the other 8 cases had multibranch defect. The nerve gap ranged from 1.5cm to 3.0 cm. After both the proximal and the distal segment had been dissected,the nerve was elongated by the expander designed and manufactured. The expansionwas done at a speed of 2.0 cm/30 min, and it lasted until the end-to-end neurorrhaphy can be done easily. The treatment result was evaluated according to Baker’s classification and HouseBrackmann’s grading system. Results Nine patients were followed up 618 months. In 5 cases achieving good result, both dynamic look and static look of face were symmetric, the EMG peak value of mimetic muscle was 82%95% of normal side. In 3 cases achieving fair result, thedynamic look and static look of face were basically symmetric, and the EMG peak value of mimetic muscle was 60%90% of normal side. In 1 case achieving poor result, the function of mimetic muscle was improved slightly, and the EMG peak value of mimetic muscle was 55% of normal side. Conclusion The satisfactory resultcan be obtained by endtoend neurorrhaphy following rapid expansion of the nerve in condition that nerve defect is less than 3.0 cm.
OBJECTIVE: To evaluate the nerve regeneration after implantation of chitin tubes containing nerve growth factor(NGF) in the rabbit facial nerve. METHODS: Bilateral 8 mm defect of superior buccal divisions of the facial nerves were made in 16 New Zealand rabbits. Chitin tubes containing NGF were implanted into the gaps, and autologous nerves were implanted into the right gaps as control. The nerve regeneration was evaluated with electrophysiological and ultrastructural examination after 8 and 16 weeks of operation. RESULTS: Chitin tubes containing NGF successfully induced the nerve regeneration, regularly arranged myelinated and unmyelinated axons could be observed across the 8 mm gaps, and the myelin sheath was thick with clear lamellar structure at 8 weeks after operation, The regenerated nerve fibers increased and were more mature at 16 weeks after operation. There were no significant difference in electrical impulse conduction velocity through the neural regeneration between the experimental and control sides (P gt; 0.05). CONCLUSION: Chitin tubes containing NGF can provide optimal conditions for regeneration of rabbit facial nerve.
Objective To evaluate the therapeutic effect and complications of modified surgical treatment for parotid benign tumors. Methods Forty-nine patients with parotid tumors treated between February 2007 and February 2013 were randomly divided improved surgery group (trial group,n=24) and traditional surgery group (control group,n=25). Follow-up lasted from two months to two years after surgery. Postoperative complications (facial paralysis, Fery’s syndrome, local deformity, and salivary fistula) and recurrence were observed and compared between the two groups. Results All the 49 patients were followed up from two months to one year after surgery. Two years after surgery, three patients in the trial group and four in the control group were missing during the follow-up. No recurrence occurred in all the patients. There were no permanent facial paralysis cases in both groups. No temporary facial paralysis occurred in the trial group, while there were five such cases in the control group with an incidence rate of 20.0%. The trial group had one case of Fery’s syndrome with an incidence rate of 4.2%, and the control group had 4 such cases with an incidence rate of 16.0%. After surgery, the 24 patients in the trail group achieved general facial symmetry without any facial depression deformity, while there were 3 cases of mild facial depression and 1 obvious facial depression in the control group with an incidence rate of 16.0%. Five patients in the control group had saliva fistula with an incidence rate of 24.0% while one in the trail group (4.2%). The differences in the total rate of complications occurrence between the two groups were statistically significant (P<0.05). Conclusion The improved surgical treatment can effectively reduce complications after surgery for parotid benign tumors, which is worthy of clinical promotion.